1

Heat oil in 12" skillet over medium high heat until hot; add onion and sugar. Cook onion, stirring occasionally, until it begins to soften but not brown, 4-5 minutes. Add vinegar and cook until onions are soft, 2-3 minutes. Add tomatoes and cook, stirring, until they just begin to soften, 1-2 minutes. Remove the skillet from the heat, stir in the basil, and season the mixture to taste with salt and pepper. Transfer the mixture to a bowl and keep warm.

2

Season steaks generously on both sides with salt and pepper. Wipe out the skillet and melt the butter in the skillet over medium-high heat. Cook two of the steaks until nicely browned on both sides and cooked to your liking, about 3 minutes per side for medium rare.

3

Transfer steaks to plates or a platter and keep warm while you cook the remaining two steaks. Serve steaks topped with onion and tomato salsa.